Copper nanoclusters as a turn-on fluorescent probe for sensitive and selective detection of quinolones

• Published in: Microchemical journal 2021-05, Vol.164, p.105989, Article 105989
• Main Authors: Lian, Ning, Zhang, Yaheng, Liu, Dan, Tang, Jianghong, Wu, Haiyan
• Format: Article
• Language: English
• Subjects: Cu nanoclusters; Fluorescence; Quench; Quinolones; Turn on sensor
• ISSN: 0026-265X; 1095-9149
• DOI: 10.1016/j.microc.2021.105989

[Display omitted] •Ratio fluorescent nanoprobe for Fe3+-based quinolones detection was established.•The response to quinolones is based on fluorescence “turn-on” sensor.•This sensing system has good sensitivity and selectivity to quinolones.•This probe was applied to detect quinolones in tablets and human urine. As a new type of fluorescent probe, metal nanoclusters have a broad application prospect in optical sensors and biosensors. In the present study, copper nanoclusters (CuNCs) have been synthesized by etching non-luminescent copper nanoparticles with excess cysteine (Cys). The as-prepared cysteine stabilized turquoise emitting copper nanocluster (Cys-CuNCs) exhibited strong fluorescence emission, and could be quenched by Fe3+ ions. After adding quinolones (QNs) to the quenching system, the fluorescence intensity of Cys-CuNCs was restored. A novel Cys-CuNCs-Fe3+ sensor for the detection of QNs, such as ofloxacin (OFL) and norfloxacin (NOR), was constructed based on the fluorescence turn-on strategy. The linear range of the proposed method is 0.5–40 μM for OFL and 0.5–50 μM for NOR, and the detection limits of OFL and NOR are all 50 nM. As a cost-effective, high selectivity and sensitivity sensor tool, the Cys-CuNCs-Fe3+ sensor had been successfully applied to detect QNs in tablets and human urine.